Yes, I am under the impression that the group I have is genuine. 
Still, I am trying to make this as good as I can, and stack the deck in my favor as much as possible.
Another question, the transformer I have has 30v secondaries, which will be a little too hot for the inputs of the regulators... Is there any reason why I can't make a CRC filter before the Pearl boards to throw away a couple of volts?
Still, I am trying to make this as good as I can, and stack the deck in my favor as much as possible.
Another question, the transformer I have has 30v secondaries, which will be a little too hot for the inputs of the regulators... Is there any reason why I can't make a CRC filter before the Pearl boards to throw away a couple of volts?
In the original Pearl, yes. In the Pearl 2, it calls for 22v. The problem is the on-board regulators have a max input of 40v.
sorry , my bad
I found schm here : http://www.diyaudio.com/forums/pass-labs/156397-pearl-two-12.html#post2224180
according to that schm , just increase values of R1 & R2 , same as R30 & R32 ;
if you have handy values of current drawn for both polarities , I can calc how much you need to increase them ;
if you don't know currents , just say and I'll do my usual mumbojumbo analyze (Futile Attempts Method by ZM ) ......
I found schm here : http://www.diyaudio.com/forums/pass-labs/156397-pearl-two-12.html#post2224180
according to that schm , just increase values of R1 & R2 , same as R30 & R32 ;
if you have handy values of current drawn for both polarities , I can calc how much you need to increase them ;
if you don't know currents , just say and I'll do my usual mumbojumbo analyze (Futile Attempts Method by ZM ) ......
that was slow teleporting routine , fer sure ! I started as Spock , now I'm ... ?
offtopicking again , my cher Jaccolina ?
I'm catching with both my ishyaticus , regular ZM-frenia and lack of sleep and lag jet ;
(I told ya - 4 , not both
)
last 110km from Hu border to my place , which I made driving my own car - I had to stop 3 times for chill nicotine shot , just to stay awake ....
life is good , having , or not having -Pearl Two current consumption in back of brain
offtopicking again , my cher Jaccolina ?
I'm catching with both my ishyaticus , regular ZM-frenia and lack of sleep and lag jet ;
(I told ya - 4 , not both
)last 110km from Hu border to my place , which I made driving my own car - I had to stop 3 times for chill nicotine shot , just to stay awake ....
life is good , having , or not having -Pearl Two current consumption in back of brain
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Jacco - you are talking about rectification noise and ripple reduction? '1 time' = CRC and '2 times' = CRCRC?
I didn't know that a second time added that much reduction in noise... Cool!
Still, I am mainly interested to reduce voltage to input of regulator. Noise reduction in PSU will be a nice side-effect.
I didn't know that a second time added that much reduction in noise... Cool!
Still, I am mainly interested to reduce voltage to input of regulator. Noise reduction in PSU will be a nice side-effect.
Yes.
How it's in my phono stage, several filter sections before the voltage regulator stage.
(not IC ones such as the 7*24 in the Pearl2, but same-same effect. formerly known as Classé Omega phono stage, fwiw)
Sounds better (on top of using r-cores with a choke filter in front)
How it's in my phono stage, several filter sections before the voltage regulator stage.
(not IC ones such as the 7*24 in the Pearl2, but same-same effect. formerly known as Classé Omega phono stage, fwiw)
Sounds better (on top of using r-cores with a choke filter in front)
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Hi 6L6
As brothers in arms (if I may) on the F5 build
I had CRCLRC on my F5
Much easier to make your own chokes for low current such as Pearl (30 mA is this correct?)
Also the resistor part can have larger values whitout wasting to much heath.
Then maybe as Jacco mention cascade 2 regulators such as LM317 and then 7824 or even beter less noisy stuff out there.
But then why not a Shunty as Maighty Zen or one of Salas circuits?
Even beter (for my own personal amusment) if possible why not drop rails to +12 -12 if compromise in sound and overload margin is not to much.
No mains hum and nastiness from outside world getting there (apart from when charging up) just jhonson noise from batteries...
I am to much of nuts and bolts sorta chap but maybe is possible and then even beter to get Jfets on imput working at 3 volts so no hot carriers develop.
Yes possible but far out of my expertise so I may have to just use 4 LAC instead of the 2 I have already
As brothers in arms (if I may) on the F5 build
I had CRCLRC on my F5
Much easier to make your own chokes for low current such as Pearl (30 mA is this correct?)
Also the resistor part can have larger values whitout wasting to much heath.
Then maybe as Jacco mention cascade 2 regulators such as LM317 and then 7824 or even beter less noisy stuff out there.
But then why not a Shunty as Maighty Zen or one of Salas circuits?
Even beter (for my own personal amusment) if possible why not drop rails to +12 -12 if compromise in sound and overload margin is not to much.
No mains hum and nastiness from outside world getting there (apart from when charging up) just jhonson noise from batteries...
I am to much of nuts and bolts sorta chap but maybe is possible and then even beter to get Jfets on imput working at 3 volts so no hot carriers develop.
Yes possible but far out of my expertise so I may have to just use 4 LAC instead of the 2 I have already
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The 10dB in my earlier posts should of course be read as 20dB per decade for a single RC, aka -6dB for twice the frequency (similar but inverse relationship as voltage jumps)
So two consecutive RC's make 40dB reduction for each decade.
I've got the flu (going away present of NP ?), makes me write jibberish.
Oh Yeah, use 50 times higher values for a 0.05Hz corner.
Smashing.
(all three parts of ZM arrived safely and properly reconnected ? )
Sorry Jacco still refering about output caps?
I tend not to post while on local (Greenwich) public libray times so I might have miss the beat.
Quote>The 10dB in my earlier posts should of course be read as 20dB per decade for a single RC, aka -6dB for twice the frequency (similar but inverse relationship as voltage jumps)
So two consecutive RC's make 40dB reduction for each decade.
I've got the flu (going away present of NP ?), makes me write jibberish
Jacco we shall let you off today and as public library is closed, looks like you got away with this.
Do that beween 10 and 12 in the morning and it would have been mucho serious.
6L6
I am going to try out Pearl 2 myself and maybe a few more if I get permission.
I was just thinking about using what I have at present and as the one that I had before was a 8 leghed kind of creature Battery and charger + box and such is already there.
I can't comit to final build so far as natural progression for me wuld have to be a decent Preamplifier.
WFE factor demand less boxes more ornament space.
I have already Sallas Simplistic MC running on batteries so sorry for the diversion
Non whitstanding that we have 0.47 R on the CRC of the F5 maybe 4.7R beween C and C and C will do you well
Again in my personal case I already have a third plug on the F5 PSU just handy to try things out.
And then proper build (thats why I was triing to save same dosh on caps as electrolitic as coupling do not agree with me)
Bit like drinking Ripasso it gives me head ake.
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